> Cool. Sorry to be pestering about the 64-bit limits, but can we really
> use 2^64 bytes of memory on ia64/ppc64/x86-64 etc.? (AFAIK, 64-bit
> arches don't suffer from a small ZONE_LOWMEM.)
No. The hardware have far smaller physical limits.
Current AMD64 CPUs are limited to 40bit physical, 48bit virtal
(the virtual limit per process in the current Linux kernel is 39bits)
Itanium 2 afaik support a bit more 50bits (51 or 52, I forgot) physical,
probably more virtual.
Other 64bit architectures are somewhere inbetween.
The actual limit in the machines is even less. You will have a hard
time to find an affordable machine (64bit or not) with more than 8 DIMM
slots. That's 16GB Max with 2GB DIMMs.
-Andi
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Wed Apr 30 2003 - 22:00:30 EST